Metheny and Mehldau worked admirably together on their recent guitar-piano duets, but this quartet track with Larry Grenadier and Jeff Ballard reaches an even higher plateau. Metheny takes one of his great melodic solos on "A Night Away," and he continues to impress me with his ability to sublimate technique and ego in order to elevate the musicality of any given performance. Guitarists often play as if they are getting paid piece rate by the note, but Metheny is cut from a different cloth. If you listen to this track a few times, you will start humming along with his solo. Mehldau starts his improvisation in a similar vein, but soon begins pushing against the grain of the chords, stretching the aural sensibility of the composition. But you can tell that the pianist was enjoying the proceedings. He even is shown chuckling to himself on the back cover of the CD -- and jazz fans know that no artist since Miles has given fewer smiles on his promo photos than the serious Mr. Mehldau. Listeners, for their part, will find it hard to be glum when these two artists join forces.